Protein mixtures for maize insect control

ABSTRACT

Embodiments of the present invention relate to insecticidal  Bacillus thuringiensis  Cry1 and Cry2 polypeptides. Methods for using the polypeptides and nucleic acids of embodiments of the invention to synergistically enhance resistance of plants to insect predation are encompassed in embodiments of the present invention.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. §119 to provisionalapplication Ser. No. 61/146,875 filed Jan. 23, 2009, herein incorporatedby reference in its entirety.

FIELD OF THE INVENTION

Embodiments of the present invention relate generally to the field ofpest control, providing insecticidal polypeptides related tocombinations of Bacillus thuringiensis (B. t.) Cry1 and Cry2polypeptides and the polynucleotides that encode them. Embodiments ofthe present invention also relate to methods and compositions forimproved resistance of plants to insect predation, including, but notlimited to, transgenic plant production. The Cry1 and Cry2 polypeptidemixtures provide improved insecticidal activity and synergism againstkey plant pests, including maize pests.

BACKGROUND OF THE INVENTION

Numerous commercially valuable plants, including common agriculturalcrops, are susceptible to attack by insect and nematode pests, causingsubstantial reductions in crop yield and quality. For example, growersof maize (Zea mays), commonly referred to as corn in the United States,face a major problem with combating pest infestations. Insects,nematodes, and related arthropods annually destroy an estimated 15% ofagricultural crops in the United States and an even greater percentagein developing countries. In addition, competition with weeds andparasitic and saprophytic plants account for even more potential yieldlosses. Yearly, such pests cause over $100 billion in crop damage in theUnited States alone.

In an effort to combat pest infestations, various methods have beenemployed in order to reduce or eliminate pests in a particular plot.These efforts include rotating corn with other crops that are not a hostfor a particular pest and applying pesticides to the above-groundportion of the crop, applying pesticides to the soil in and around theroot systems of the affected crop. Traditionally, farmers have reliedheavily on chemical pesticides to combat pest damage. However, the useof chemical pesticides is costly, as farmers apply billions of gallonsof synthetic pesticides to combat these pests each growing season,costing nearly $8 billion. In addition, such pesticides are inconvenientfor farmers, result in the emergence of insecticide-resistant pests, andthey raise significant environmental and health concerns.

Because of concern about the impact of pesticides on public health andthe health of the environment, significant efforts have been made tofind ways to reduce the amount of chemical pesticides that are used.Recently, much of this effort has focused on the development oftransgenic crops that are engineered to express insect toxicants derivedfrom microorganisms. For example, U.S. Pat. No. 5,877,012 to Estruch etal. discloses the cloning and expression of proteins from such organismsas Bacillus, Pseudomonas, Clavibacter and Rhizobium into plants toobtain transgenic plants with resistance to such pests as blackcutworms, armyworms, several borers and other insect pests. PublicationWO/EP97/07089 by Privalle et al. teaches the transformation ofmonocotyledons, such as corn, with a recombinant DNA sequence encodingperoxidase for the protection of the plant from feeding by corn borers,earworms and cutworms. Jansens et al., Crop Sci., 37(5):1616-1624(1997), reported the production of transgenic corn containing a geneencoding a crystalline protein from Bt that controlled both generationsof Eastern Corn Borer (ECB). U.S. Pat. Nos. 5,625,136 and 5,859,336 toKoziel et al. reported that the transformation of corn with a gene fromBt that encoded for a δ-endotoxin provided the transgenic corn withimproved resistance to ECB. Additionally, a comprehensive report offield trials of transgenic corn that expresses an insecticidal proteinfrom Bt has been provided by Armstrong et al., Crop Science,35(2):550-557 (1995).

For these and other reasons, there is a demand for alternativeinsecticidal agents for agricultural crops. For example, maize plantsincorporating transgenic genes which cause the maize plant to produceinsecticidal proteins providing protection from the target pest(s) is amore environmentally friendly approach to controlling pests. The use ofpesticidal crystal proteins derived from the soil bacterium Bt commonlyreferred to as “Cry proteins” have been utilized. Cry proteins areglobular protein molecules which accumulate as protoxins in crystallineform during late stage of the sporulation of Bt. After ingestion by thepest, the crystals are solubilized to release protoxins in the alkalinemidgut environment of the larvae. Protoxins (˜130 kDa) are convertedinto mature toxic fragments (˜66 kDa N terminal region) by gutproteases. Many of these proteins are quite toxic to specific targetinsects, but harmless to plants and other non-targeted organisms. SomeCry proteins have been recombinantly expressed in crop plants to providepest-resistant transgenic plants. Among those, Bt-transgenic cotton andcorn have been widely cultivated.

A large number of Cry proteins have been isolated, characterized andclassified based on amino acid sequence homology. See Crickmore et al.,Microbiol. Mol. Biol. Rev., 62:807-813 (1998). This classificationscheme provides a systematic mechanism for naming and categorizing newlydiscovered Cry proteins. Bt toxins have traditionally been categorizedby their specific toxicity towards specific insect categories. Forexample, the Cry1 group of toxins is toxic to Lepidoptera, and includes,but is not limited to, Cry1Aa, Cry1Ab and Cry1Ac. See Hofte et al.,Microbiol. Rev., 53:242-255 (1989). The Cry1 classification is the bestknown and contains the highest number of cry genes, currently totalsover 130. Cry1 and Cry2 proteins share a minimal amount of sequencehomology. See, e.g., Crickmore et al. (1998) indicating that Cry1A andCry2A classes are among the most divergent.

It has generally been found that individual Cry proteins possessrelatively narrow activity spectra. For example, Cry1Ac was the firsttoxin to be deployed in transgenic cotton for control of H. virescensand H. zea insect pests. This toxin is known for its high level toxicityto H. virescens. However, it is slightly deficient in its ability tocontrol H. zea and has almost no activity on Spodoptera species.Additionally, Cry1Ab toxin has slightly less activity on H. zea thanCry1Ac but has far superior activity against S. exigua.

Cry2A is an exception as it is unusual in that this subset of Cryproteins possesses a broader effective range that includes toxicity toboth the Lepidoptera and Diptera orders of insects. The Cry2A proteinwas discovered to be a toxin showing a dual activity againstTrichoplusia ni (cabbage looper) and Aedes taeniorhynchus (mosquito)(Yamamoto & McLaughlin, Biochem. Biophys. Res. Comm., 130:414-421(1982)). The nucleic acid molecule encoding the Cry2A protein (termedCry2Aa) was cloned and expressed in B. megaterium and found to be activeagainst both Lepidoptera and Diptera insects (Donovan et al., J.Bacteriol., 170:4732-4738 (1988)). An additional coding sequencehomologous to Cry2Aa was cloned (termed Cry2Ab) and was found to beactive only against Lepidoptera larvae (Widner & Whiteley, J.Bacteriol., 171(2):965-974 (1989)).

Second generation transgenic crops could be more resistant to insects ifthey are able to express multiple, novel and/or synergistic Bt genes.

Accordingly, it is an objective of embodiments of the present inventionto provide synergistic resistance to plant insects.

Another objective of embodiments of the invention includes methods forincorporating multiple Cry proteins into transgenic plants, namelymaize.

SUMMARY OF THE INVENTION

Embodiments of the present invention relate to Cry polypeptides derivedfrom Bt Cry1 and Cry2 polypeptides and provides a novel means forimproved and synergistic insecticidal resistance against key crop pests.Embodiments of the present invention also relate to transgenic plantsexpressing such a nucleic acid and/or polypeptide. The transgenic plantscan express the transgene in any way known in the art, including, butnot limited to, constitutive expression, developmentally regulatedexpression, tissue specific expression, etc. Additionally, seed obtainedfrom a transgenic plant of the invention is also encompassed.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows the sequences for the IP1-88 and IP2-127 Cry proteins, aswell as the DNA and amino acid sequence for a Cry1 (h) protein relevantto the disclosure.

DETAILED DESCRIPTION

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which embodiments of this invention belong. Unless mentionedotherwise, the techniques employed or contemplated herein are standardmethodologies well known to one of ordinary skill in the art. Thematerials, processes and examples described in the description areillustrative only and not intended to be limiting to the scope of theclaims in any manner. Many modifications and other embodiments of theinventions set forth herein will come to mind to one skilled in the artto which these inventions pertain having the benefit of the teachingspresented in the foregoing descriptions and the associated drawings.Therefore, it is to be understood that the disclosure is not to belimited to the specific embodiments disclosed and that modifications andother embodiments are intended to be included within the scope of theappended claims.

As used herein, “pesticidal agent” or “pesticide” includes any organism,organic substance, or inorganic substance that has pesticidal activity.As used herein, the term “pesticidal activity” refers to activity of anorganism or a substance (such as, for example, a protein) that can bemeasured by, but is not limited to, pest mortality, pest weight loss,pest repellency, and other behavioral and physical changes of a pestafter feeding and exposure for an appropriate length of time. Thus, anorganism or substance having pesticidal activity adversely impacts atleast one measurable parameter of pest fitness. Preferably, pesticidalactivity results in reduced damage to a plant with such a pesticidalagent as compared with plants lacking such pesticidal agent. If thepesticidal agent's target pest is an insect, it is referred to as an“insecticide.” If the pesticidal agent's target pest is a mite, it isreferred to as an “acaricide.” If the pesticidal agent's target pest isa mite, it is referred to as a “nematicide”. If the pesticidal agent'starget pest is a fungus, it is referred to as a “fungicide.” If thepesticidal agent's target pest is a bacterium, it is referred to as a“bactericide.” If the pesticidal agent's target pest is a plant, it isreferred to as a “herbicide.”

Combinations of pesticidal agents can have one of three effects onpesticidal activity: antagonistic, additive, or synergistic. If theobserved pesticidal activity of the two pesticidal agents together isapproximately the expected pesticidal activity of the combination, thecombination is said to be “additive.” If the observed pesticidalactivity of the two pesticidal agents together is less than the expectedpesticidal activity of the combination, the combination is said to be“antagonistic.” If the observed pesticidal activity of the twopesticidal agents together is greater than the expected pesticidalactivity of the combination, the combination is said to be“synergistic.” The expected pesticidal activity for a given combinationof pesticidal agents is determined by the following method. If X is theobserved level of pesticidal activity of pesticidal agent A alone and Yis the observed level of pesticidal activity of pesticidal agent Balone, the expected pesticidal activity of pesticidal agents A and B incombination (assuming the level of pesticidal activity is measured on ascale from 0 to 100) is X+Y−(X*Y)/100.

Embodiments of the invention may show an increase of pesticidal activityof a given combination of 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 15%,20%, 25%, 30%, 35%, 40%, 45%, or 50% or greater against the insecttarget as compared to the expected pesticidal activity of thecombination.

As used herein, “nucleic acid” includes reference to adeoxyribonucleotide or ribonucleotide polymer in either single- ordouble-stranded form, and unless otherwise limited, encompasses knownanalogues (e.g., peptide nucleic acids) having the essential nature ofnatural nucleotides in that they hybridize to single-stranded nucleicacids in a manner similar to that of naturally occurring nucleotides.

As used herein, the terms “encoding” or “encoded” when used in thecontext of a specified nucleic acid mean that the nucleic acid comprisesthe requisite information to direct translation of the nucleotidesequence into a specified protein. The information by which a protein isencoded is specified by the use of codons. A nucleic acid encoding aprotein may comprise non-translated sequences (e.g., introns) withintranslated regions of the nucleic acid or may lack such interveningnon-translated sequences (e.g., as in cDNA).

The terms “polypeptide,” “peptide,” and “protein” are usedinterchangeably herein to refer to a polymer of amino acid residues. Theterms apply to amino acid polymers in which one or more amino acidresidues is an artificial chemical analogue of a corresponding naturallyoccurring amino acid, as well as to naturally occurring amino acidpolymers.

The terms “residue” or “amino acid residue” or “amino acid” are usedinterchangeably herein to refer to an amino acid that is incorporatedinto a protein, polypeptide, or peptide (collectively “protein”). Theamino acid may be a naturally occurring amino acid and, unless otherwiselimited, may encompass known analogues of natural amino acids that canfunction in a similar manner as naturally occurring amino acids.

Polypeptides of the embodiments can be produced either from a nucleicacid disclosed herein, or by the use of standard molecular biologytechniques. For example, a protein of the embodiments can be produced byexpression of a recombinant nucleic acid of the embodiments in anappropriate host cell, or alternatively by a combination of ex vivoprocedures.

The following terms are used to describe the sequence relationshipsbetween two or more nucleic acids or polynucleotides: (a) “referencesequence,” (b) “comparison window,” (c) “sequence identity,” (d)“percentage of sequence identity,” and (e) “substantial identity.”

-   -   (a) As used herein, “reference sequence” is a defined sequence        used as a basis for sequence comparison. A reference sequence        may be a subset or the entirety of a specified sequence; for        example, as a segment of a full-length cDNA or gene sequence, or        the complete cDNA or gene sequence.    -   (b) As used herein, “comparison window” makes reference to a        contiguous and specified segment of a polynucleotide sequence,        wherein the polynucleotide sequence in the comparison window may        comprise additions or deletions (i.e., gaps) compared to the        reference sequence (which does not comprise additions or        deletions) for optimal alignment of the two sequences.        Generally, the comparison window is at least 20 contiguous        nucleotides in length, and optionally can be 30, 40, 50, 100, or        longer. Those of skill in the art understand that to avoid a        high similarity to a reference sequence due to inclusion of gaps        in the polynucleotide sequence a gap penalty is typically        introduced and is subtracted from the number of matches.

Methods of alignment of sequences for comparison are well known in theart. Thus, the determination of percent sequence identity between anytwo sequences can be accomplished using a mathematical algorithm.Non-limiting examples of such mathematical algorithms are the algorithmof Myers and Miller (1988) CABIOS 4:11-17; the local alignment algorithmof Smith et al. (1981) Adv. Appl. Math. 2:482; the global alignmentalgorithm of Needleman and Wunsch (1970) J. Mol. Biol. 48:443-453; thesearch-for-local alignment method of Pearson and Lipman (1988) Proc.Natl. Acad. Sci. 85:2444-2448; the algorithm of Karlin and Altschul(1990) Proc. Natl. Acad. Sci. USA 872264, as modified in Karlin andAltschul (1993) Proc. Natl. Acad. Sci. USA 90:5873-5877.

Computer implementations of these mathematical algorithms can beutilized for comparison of sequences to determine sequence identity.Such implementations include, but are not limited to: CLUSTAL in thePC/Gene program (available from Intelligenetics, Mountain View, Calif.);the ALIGN program (Version 2.0) and GAP, BESTFIT, BLAST, FASTA, andTFASTA in the GCG Wisconsin Genetics Software Package, Version 10(available from Accelrys Inc., 9685 Scranton Road, San Diego, Calif.,USA). Alignments using these programs can be performed using the defaultparameters. The CLUSTAL program is well described by Higgins et al.(1988) Gene 73:237-244 (1988); Higgins et al. (1989) CABIOS 5:151-153;Corpet et al. (1988) Nucleic Acids Res. 16:10881-90; Huang et al. (1992)CABIOS 8:155-65; and Pearson et al. (1994) Meth. Mol. Biol. 24:307-331.The ALIGN program is based on the algorithm of Myers and Miller (1988)supra. A PAM120 weight residue table, a gap length penalty of 12, and agap penalty of 4 can be used with the ALIGN program when comparing aminoacid sequences. The BLAST programs of Altschul et al. (1990) J. Mol.Biol. 215:403 are based on the algorithm of Karlin and Altschul (1990)supra. BLAST nucleotide searches can be performed with the BLASTNprogram, score=100, wordlength=12, to obtain nucleotide sequenceshomologous to a nucleotide sequence encoding a protein of theembodiments. BLAST protein searches can be performed with the BLASTXprogram, score=50, wordlength=3, to obtain amino acid sequenceshomologous to a protein or polypeptide of the embodiments. To obtaingapped alignments for comparison purposes, Gapped BLAST (in BLAST 2.0)can be utilized as described in Altschul et al. (1997) Nucleic AcidsRes. 25:3389. Alternatively, PSI-BLAST (in BLAST 2.0) can be used toperform an iterated search that detects distant relationships betweenmolecules. See Altschul et al. (1997) supra. When utilizing BLAST,Gapped BLAST, PSI-BLAST, the default parameters of the respectiveprograms (e.g., BLASTN for nucleotide sequences, BLASTX for proteins)can be used, as described on the National Center for BiotechnologyInformation website. Alignment may also be performed manually byinspection.

Unless otherwise stated, sequence identity/similarity values providedherein refer to the value obtained using GAP Version 10 using thefollowing parameters: % identity and % similarity for a nucleotidesequence using GAP Weight of 50 and Length Weight of 3, and thenwsgapdna.cmp scoring matrix; % identity and % similarity for an aminoacid sequence using GAP Weight of 8 and Length Weight of 2, and theBLOSUM62 scoring matrix; or any equivalent program thereof. The term“equivalent program” as used herein refers to any sequence comparisonprogram that, for any two sequences in question, generates an alignmenthaving identical nucleotide or amino acid residue matches and anidentical percent sequence identity when compared to the correspondingalignment generated by GAP Version 10.

GAP uses the algorithm of Needleman and Wunsch (1970) supra, to find thealignment of two complete sequences that maximizes the number of matchesand minimizes the number of gaps. GAP considers all possible alignmentsand gap positions and creates the alignment with the largest number ofmatched bases and the fewest gaps. It allows for the provision of a gapcreation penalty and a gap extension penalty in units of matched bases.GAP must make a profit of gap creation penalty number of matches foreach gap it inserts. If a gap extension penalty greater than zero ischosen, GAP must, in addition, make a profit for each gap inserted ofthe length of the gap times the gap extension penalty. Default gapcreation penalty values and gap extension penalty values in Version 10of the GCG Wisconsin Genetics Software Package for protein sequences are8 and 2, respectively. For nucleotide sequences the default gap creationpenalty is 50 while the default gap extension penalty is 3. The gapcreation and gap extension penalties can be expressed as an integerselected from the group of integers consisting of from 0 to 200. Thus,for example, the gap creation and gap extension penalties can be 0, 1,2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65or greater.

GAP presents one member of the family of best alignments. There may bemany members of this family, but no other member has a better quality.GAP displays four figures of merit for alignments: Quality, Ratio,Identity, and Similarity. The Quality is the metric maximized in orderto align the sequences. Ratio is the quality divided by the number ofbases in the shorter segment. Percent Identity is the percent of thesymbols that actually match. Percent Similarity is the percent of thesymbols that are similar. Symbols that are across from gaps are ignored.A similarity is scored when the scoring matrix value for a pair ofsymbols is greater than or equal to 0.50, the similarity threshold. Thescoring matrix used in Version 10 of the GCG Wisconsin Genetics SoftwarePackage is BLOSUM62 (see Henikoff and Henikoff (1989) Proc. Natl. Acad.Sci. USA 89:10915).

-   -   (c) As used herein, “sequence identity” or “identity” in the        context of two nucleic acid or polypeptide sequences makes        reference to the residues in the two sequences that are the same        when aligned for maximum correspondence over a specified        comparison window. When percentage of sequence identity is used        in reference to proteins it is recognized that residue positions        which are not identical often differ by conservative amino acid        substitutions, where amino acid residues are substituted for        other amino acid residues with similar chemical properties        (e.g., charge or hydrophobicity) and therefore do not change the        functional properties of the molecule. When sequences differ in        conservative substitutions, the percent sequence identity may be        adjusted upwards to correct for the conservative nature of the        substitution. Sequences that differ by such conservative        substitutions are said to have “sequence similarity” or        “similarity”. Means for making this adjustment are well known to        those of skill in the art. Typically this involves scoring a        conservative substitution as a partial rather than a full        mismatch, thereby increasing the percentage sequence identity.        Thus, for example, where an identical amino acid is given a        score of 1 and a non-conservative substitution is given a score        of zero, a conservative substitution is given a score between        zero and 1. The scoring of conservative substitutions is        calculated, e.g., as implemented in the program PC/GENE        (Intelligenetics, Mountain View, Calif.).    -   (d) As used herein, “percentage of sequence identity” means the        value determined by comparing two optimally aligned sequences        over a comparison window, wherein the portion of the        polynucleotide sequence in the comparison window may comprise        additions or deletions (i.e., gaps) as compared to the reference        sequence (which does not comprise additions or deletions) for        optimal alignment of the two sequences. The percentage is        calculated by determining the number of positions at which the        identical nucleic acid base or amino acid residue occurs in both        sequences to yield the number of matched positions, dividing the        number of matched positions by the total number of positions in        the window of comparison, and multiplying the result by 100 to        yield the percentage of sequence identity.    -   (e)(i) The term “substantial identity” of polynucleotide        sequences means that a polynucleotide comprises a sequence that        has at least 70%, 80%, 90%, or 95% or more sequence identity        when compared to a reference sequence using one of the alignment        programs described using standard parameters. One of skill in        the art will recognize that these values can be appropriately        adjusted to determine corresponding identity of proteins encoded        by two nucleotide sequences by taking into account codon        degeneracy, amino acid similarity, reading frame positioning,        and the like. Substantial identity of amino acid sequences for        these purposes generally means sequence identity of at least        60%, 70%, 80%, 90%, or 95% or more sequence identity.

Another indication that nucleotide sequences are substantially identicalis if two molecules hybridize to each other under stringent conditions.Generally, stringent conditions are selected to be about 5° C. lowerthan the Tm for the specific sequence at a defined ionic strength andpH. However, stringent conditions encompass temperatures in the range ofabout 1° C. to about 20° C. lower than the Tm, depending upon thedesired degree of stringency as otherwise qualified herein. Nucleicacids that do not hybridize to each other under stringent conditions arestill substantially identical if the polypeptides they encode aresubstantially identical. This may occur, e.g., when a copy of a nucleicacid is created using the maximum codon degeneracy permitted by thegenetic code. One indication that two nucleic acid sequences aresubstantially identical is when the polypeptide encoded by the firstnucleic acid is immunologically cross reactive with the polypeptideencoded by the second nucleic acid.

(e)(ii) The term “substantial identity” in the context of a peptideindicates that a peptide comprises a sequence with at least 70%, 80%,85%, 90%, 95%, or more sequence identity to a reference sequence over aspecified comparison window. Optimal alignment for these purposes can beconducted using the global alignment algorithm of Needleman and Wunsch(1970) supra. An indication that two peptide sequences are substantiallyidentical is that one peptide is immunologically reactive withantibodies raised against the second peptide. Thus, a peptide issubstantially identical to a second peptide, for example, where the twopeptides differ only by a conservative substitution. Peptides that are“substantially similar” share sequences as noted above except thatresidue positions that are not identical may differ by conservativeamino acid changes.

The term “toxin” as used herein refers to a polypeptide showingpesticidal activity or insecticidal activity or improved pesticidalactivity or improved insecticidal activity. “Bt” or “Bacillusthuringiensis” toxin is intended to include the broader class of Crytoxins found in various strains of Bt, which includes such toxins as,for example, Cry1s, Cry2s, or Cry3s.

The terms “proteolytic site” or “cleavage site” refer to an amino acidsequence which confers sensitivity to a class of proteases or aparticular protease such that a polypeptide containing the amino acidsequence is digested by the class of proteases or particular protease. Aproteolytic site is said to be “sensitive” to the protease(s) thatrecognize that site. It is appreciated in the art that the efficiency ofdigestion will vary, and that a decrease in efficiency of digestion canlead to an increase in stability or longevity of the polypeptide in aninsect gut. Thus, a proteolytic site may confer sensitivity to more thanone protease or class of proteases, but the efficiency of digestion atthat site by various proteases may vary. Proteolytic sites include, forexample, trypsin sites, chymotrypsin sites, and elastase sites.

Research has shown that the insect gut proteases of Lepidopteransinclude trypsins, chymotrypsins, and elastases. See, e.g., Lenz et al.(1991) Arch. Insect Biochem. Physiol. 16: 201-212; and Hedegus et al.(2003) Arch. Insect Biochem. Physiol. 53: 30-47. For example, about 18different trypsins have been found in the midgut of Helicoverpa armigeralarvae (see Gatehouse et al. (1997) Insect Biochem. Mol. Biol. 27:929-944). The preferred proteolytic substrate sites of these proteaseshave been investigated. See, e.g., Peterson et al. (1995) InsectBiochem. Mol. Biol. 25: 765-774.

Efforts have been made to understand the mechanism of action of Bttoxins and to engineer toxins with improved properties. It has beenshown that insect gut proteases can affect the impact of Bt Cry proteinson the insect. Some proteases activate the Cry proteins by processingthem from a “protoxin” form into a toxic form, or “toxin.” See Oppert(1999) Arch. Insect Biochem. Phys. 42: 1-12; Carroll et al. (1997) J.Invertebrate Pathology 70: 41-49. This activation of the toxin caninclude the removal of the N- and C-terminal peptides from the proteinand can also include internal cleavage of the protein. Other proteasescan degrade the Cry proteins. See Oppert, ibid.

A comparison of the amino acid sequences of Cry toxins of differentspecificities reveals five highly-conserved sequence blocks.Structurally, the toxins comprise three distinct domains which are, fromthe N- to C-terminus: a cluster of seven alpha-helices implicated inpore formation (referred to as “domain 1”), three anti-parallel betasheets implicated in cell binding (referred to as “domain 2”), and abeta sandwich (referred to as “domain 3”). The location and propertiesof these domains are known to those of skill in the art. See, e.g., Liet al. (1991) Nature, 305:815-821; Morse et al. (2001) Structure,9:409-417. When reference is made to a particular domain, such as domain1, it is understood that the exact endpoints of the domain with regardto a particular sequence are not critical so long as the sequence orportion thereof includes sequence that provides at least some functionattributed to the particular domain. Thus, for example, when referringto “domain 1,” it is intended that a particular sequence includes acluster of seven alpha-helices, but the exact endpoints of the sequenceused or referred to with regard to that cluster are not critical. One ofskill in the art is familiar with the determination of such endpointsand the evaluation of such functions.

In an effort to better characterize and improve Bt toxins, strains ofthe bacterium Bt have been studied. An effort was undertaken to identifythe nucleotide sequences encoding the crystal proteins from the selectedstrains, and the wild-type (i.e., naturally occurring) nucleic acids ofthe embodiments were isolated from these bacterial strains, cloned intoan expression vector, and transformed into E coli. Depending upon thecharacteristics of a given preparation, it was recognized that thedemonstration of pesticidal activity sometimes required trypsinpretreatment to activate the pesticidal proteins. Thus, it is understoodthat some pesticidal proteins require protease digestion (e.g., bytrypsin, chymotrypsin, and the like) for activation, while otherproteins are biologically active (e.g., pesticidal) in the absence ofactivation.

Such molecules may be altered by means described, for example, in U.S.application Ser. No. 10/606,320, filed Jun. 25, 2003, and Ser. No.10/746,914, filed Dec. 24, 2003. In addition, nucleic acid sequences maybe engineered to encode polypeptides that contain additional mutationsthat confer improved or altered pesticidal activity relative to thepesticidal activity of the naturally occurring polypeptide. Thenucleotide sequences of such engineered nucleic acids comprise mutationsnot found in the wild type sequences.

The mutant polypeptides of the embodiments are generally prepared by aprocess that involves the steps of: obtaining a nucleic acid sequenceencoding a Cry family polypeptide; analyzing the structure of thepolypeptide to identify particular “target” sites for mutagenesis of theunderlying gene sequence based on a consideration of the proposedfunction of the target domain in the mode of action of the toxin;introducing one or more mutations into the nucleic acid sequence toproduce a desired change in one or more amino acid residues of theencoded polypeptide sequence; and assaying the polypeptide produced forpesticidal activity.

Many of the Bt insecticidal toxins are related to various degrees bysimilarities in their amino acid sequences and tertiary structure andmeans for obtaining the crystal structures of Bt toxins are well known.Exemplary high-resolution crystal structure solution of both the Cry3Aand Cry3B polypeptides are available in the literature. The solvedstructure of the Cry3A gene (Li et al. (1991) Nature 353:815-821)provides insight into the relationship between structure and function ofthe toxin. A combined consideration of the published structural analysesof Bt toxins and the reported function associated with particularstructures, motifs, and the like indicates that specific regions of thetoxin are correlated with particular functions and discrete steps of themode of action of the protein. For example, many toxins isolated from Btare generally described as comprising three domains: a seven-helixbundle that is involved in pore formation, a three-sheet domain that hasbeen implicated in receptor binding, and a beta-sandwich motif (Li etal. (1991) Nature 305: 815-821).

As reported in U.S. Pat. No. 7,105,332, and pending U.S. applicationSer. No. 10/746,914, filed Dec. 24, 2003, the toxicity of Cry proteinscan be improved by targeting the region located between alpha helices 3and 4 of domain 1 of the toxin. This theory was premised on a body ofknowledge concerning insecticidal toxins, including: 1) that alphahelices 4 and 5 of domain 1 of Cry3A toxins had been reported to insertinto the lipid bilayer of cells lining the midgut of susceptible insects(Gazit et al. (1998) Proc. Natl. Acad. Sci. USA 95: 12289-12294); 2) theinventors' knowledge of the location of trypsin and chymotrypsincleavage sites within the amino acid sequence of the wild-type protein;3) the observation that the wild-type protein was more active againstcertain insects following in vitro activation by trypsin or chymotrypsintreatment; and 4) reports that digestion of toxins from the 3′ endresulted in decreased toxicity to insects.

A series of mutations may be created and placed in a variety ofbackground sequences to create novel polypeptides having enhanced oraltered pesticidal activity. See, e.g., U.S. application Ser. No.10/606,320, filed Jun. 25, 2003, now abandoned, and Ser. No. 10/746,914,filed Dec. 24, 2003. These mutants include, but are not limited to: theaddition of at least one more protease-sensitive site (e.g., trypsincleavage site) in the region located between helices 3 and 4 of domain1; the replacement of an original protease-sensitive site in thewild-type sequence with a different protease-sensitive site; theaddition of multiple protease-sensitive sites in a particular location;the addition of amino acid residues near protease-sensitive site(s) toalter folding of the polypeptide and thus enhance digestion of thepolypeptide at the protease-sensitive site(s); and adding mutations toprotect the polypeptide from degradative digestion that reduces toxicity(e.g., making a series of mutations wherein the wild-type amino acid isreplaced by valine to protect the polypeptide from digestion). Mutationsmay be used singly or in any combination to provide polypeptides of theembodiments.

In this manner, the embodiments provide sequences comprising a varietyof mutations, such as, for example, a mutation that comprises anadditional, or an alternative, protease-sensitive site located betweenalpha-helices 3 and 4 of domain 1 of the encoded polypeptide. A mutationwhich is an additional or alternative protease-sensitive site may besensitive to several classes of proteases such as serine proteases,which include trypsin and chymotrypsin, or enzymes such as elastase.Thus, a mutation which is an additional or alternativeprotease-sensitive site may be designed so that the site is readilyrecognized and/or cleaved by a category of proteases, such as mammalianproteases or insect proteases. A protease-sensitive site may also bedesigned to be cleaved by a particular class of enzymes or a particularenzyme known to be produced in an organism, such as, for example, achymotrypsin produced by the corn earworm Heliothis zea (Lenz et al.(1991) Arch. Insect Biochem. Physiol. 16: 201-212). Mutations may alsoconfer resistance to proteolytic digestion, for example, to digestion bychymotrypsin at the C-terminus of the peptide.

The presence of an additional and/or alternative protease-sensitive sitein the amino acid sequence of the encoded polypeptide can improve thepesticidal activity and/or specificity of the polypeptide encoded by thenucleic acids of the embodiments. Accordingly, the nucleotide sequencesof the embodiments can be recombinantly engineered or manipulated toproduce polypeptides having improved or altered insecticidal activityand/or specificity compared to that of an unmodified wild-type toxin. Inaddition, mutations may be placed in or used in conjunction with othernucleotide sequences to provide improved properties. For example, aprotease-sensitive site that is readily cleaved by insect chymotrypsin,e.g., a chymotrypsin found in the bertha armyworm or the corn earworm(Hegedus et al. (2003) Arch. Insect Biochem. Physiol. 53: 30-47; andLenz et al. (1991) Arch. Insect Biochem. Physiol. 16: 201-212), may beplaced in a Cry background sequence to provide improved toxicity to thatsequence. In this manner, the embodiments provide toxic polypeptideswith improved properties.

For example, a mutagenized Cry nucleotide sequence can compriseadditional mutants that comprise additional codons that introduce asecond trypsin-sensitive amino acid sequence (in addition to thenaturally occurring trypsin site) into the encoded polypeptide. Analternative addition mutant of the embodiments comprises additionalcodons designed to introduce at least one additional differentprotease-sensitive site into the polypeptide, for example, achymotrypsin-sensitive site located immediately 5′ or 3′ of thenaturally occurring trypsin site. Alternatively, substitution mutantsmay be created in which at least one codon of the nucleic acid thatencodes the naturally occurring protease-sensitive site is destroyed andalternative codons are introduced into the nucleic acid sequence inorder to provide a different (e.g., substitute) protease-sensitive site.A replacement mutant may also be added to a Cry sequence in which thenaturally-occurring trypsin cleavage site present in the encodedpolypeptide is destroyed and a chymotrypsin or elastase cleavage site isintroduced in its place.

It is recognized that any nucleotide sequence encoding the amino acidsequences that are proteolytic sites or putative proteolytic sites (forexample, sequences such as NGSR, RR, or LKM) can be used and that theexact identity of the codons used to introduce any of these cleavagesites into a variant polypeptide may vary depending on the use, i.e.,expression in a particular plant species. It is also recognized that anyof the disclosed mutations can be introduced into any polynucleotidesequence of the embodiments that comprises the codons for amino acidresidues that provide the native trypsin cleavage site that is targetedfor modification. Accordingly, variants of either full-length toxins orfragments thereof can be modified to contain additional or alternativecleavage sites, and these embodiments are intended to be encompassed bythe scope of the embodiments disclosed herein.

It will be appreciated by those of skill in the art that any usefulmutation may be added to the sequences of the embodiments so long as theencoded polypeptides retain pesticidal activity. Thus, sequences mayalso be mutated so that the encoded polypeptides are resistant toproteolytic digestion by chymotrypsin. More than one recognition sitecan be added in a particular location in any combination, and multiplerecognition sites can be added to or removed from the toxin. Thus,additional mutations can comprise three, four, or more recognitionsites. It is to be recognized that multiple mutations can be engineeredin any suitable polynucleotide sequence; accordingly, either full-lengthsequences or fragments thereof can be modified to contain additional oralternative cleavage sites as well as to be resistant to proteolyticdigestion. In this manner, the embodiments provide Cry toxins containingmutations that improve pesticidal activity as well as improvedcompositions and methods for impacting pests using other Bt toxins.

Mutations may protect the polypeptide from protease degradation, forexample by removing putative proteolytic sites such as putative serineprotease sites and elastase recognition sites from different areas. Someor all of such putative sites may be removed or altered so thatproteolysis at the location of the original site is decreased. Changesin proteolysis may be assessed by comparing a mutant polypeptide withwild-type toxins or by comparing mutant toxins which differ in theiramino acid sequence. Putative proteolytic sites and proteolytic sitesinclude, but are not limited to, the following sequences: RR, a trypsincleavage site; LKM, a chymotrypsin site; and NGSR, a trypsin site. Thesesites may be altered by the addition or deletion of any number and kindof amino acid residues, so long as the pesticidal activity of thepolypeptide is increased. Thus, polypeptides encoded by nucleotidesequences comprising mutations will comprise at least one amino acidchange or addition relative to the native or background sequence, or 2,3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,23, 24, 25, 26, 27, 28, 29, 30, 32, 35, 38, 40, 45, 47, 50, 60, 70, 80,90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220,230, 240, 250, 260, 270, or 280 or more amino acid changes or additions.Pesticidal activity of a polypeptide may also be improved by truncationof the native or full-length sequence, as is known in the art.

Embodiments of the present invention provide insecticidal polypeptidesrelated to Bt Cry1 and Cry2 polypeptides. Nucleic acid moleculesencoding the polypeptides are also provided. Methods for using thepolypeptides and nucleic acids to enhance resistance of plants to insectpredation are encompassed.

The combination of a Cry1 and Cry2 protein yields a synergistic effectagainst a plurality of target pests, providing greater than expectedmortality and/or resistance to a plurality of target pests. Prior arthas in fact taught away from the disclosed embodiments, indicating thatsynergism is not an expected outcome for insecticidal activity. Othersskilled in the art have indicated that such combinations result in theantagonism, rather than synergism, effect on Helicoverpa armigera (Liao,C. et al., Toxicity of B. thuringiensis insecticidal proteins ofHelicoverpa armigera and H. punctigera, major pests of cotton, J.Invertebrate Pathology 80:55-63 (2002)). Others have found reportedtests using Cry1 and Cry2 proteins with reported synergism effects (Dinget al., Expression and synergism of two cry insecticidal protein genesin P. fluorescens, Chinese J. of Microbiol., 40:573-578 (2000)).

Methods of Enhancing Insect Resistance in Plants

Embodiments of the present invention provide methods of enhancing plantresistance to insect pests including, but not limited to, members oforder Lepidoptera, the Helicoverpa ssp. (e.g., Helicoverpa Zea andHeliothis virescens), and/or Spodoptera ssp. (e.g., Spodoptera exigua,Spodoptera frugiperda) through the use of Cry1-derived insecticidalpolypeptides combined with Cry2-derived insecticidal polypeptides toproduce a synergistic effect. Any method known in the art can be used tocause the insect pests to ingest one or more polypeptides during thecourse of feeding on the plant. As such, the insect pest will ingestinsecticidal amounts of the one or more polypeptides of embodiments ofthe invention and may discontinue feeding on the plant. In someembodiments, the insect pest is killed by ingestion of the one or morepolypeptides. In other embodiments, the insect pests are inhibited ordiscouraged from feeding on the plant without being killed.

In one embodiment, transgenic plants can be made to express one or morepolypeptides. The transgenic plant may express the one or morepolypeptides in all tissues (e.g., global expression). Alternatively,the one or more polypeptides may be expressed in only a subset oftissues (e.g., tissue specific expression), preferably those tissuesconsumed by the insect pest. Polypeptides that are embodiments of theinvention can be expressed constitutively in the plant or be under thecontrol of an inducible promoter. Polypeptides that are embodiments ofthe invention may be expressed in the plant cytosol or in the plantchloroplast either by protein targeting or by transformation of thechloroplast genome.

In another embodiment, a composition comprising one or more polypeptidesof embodiments of the invention can be applied externally to a plantsusceptible to the insect pests. External application of the compositionincludes direct application to the plant, either in whole or in part,and/or indirect application, e.g., to the environment surrounding theplant such as the soil. The composition can be applied by any methodknown in the art including, but not limited to, spraying, dusting,sprinkling, or the like. In general, the composition can be applied atany time during plant growth. One skilled in the art can use methodsknown in the art to determine empirically the optimal time foradministration of the composition. Factors that affect optimaladministration time include, but are not limited to, the type ofsusceptible plant, the type of insect pest, which one or morepolypeptides are administered in the composition.

The composition comprising one or more polypeptides may be substantiallypurified polypeptides, a cell suspension, a cell pellet, a cellsupernatant, a cell extract, or a spore-crystal complex of Bt cells. Thecomposition comprising one or more polypeptides embodying the inventionmay be in the form of a solution, an emulsion, a suspension, or apowder. Liquid formulations may be aqueous or non-aqueous based and maybe provided as foams, gels, suspensions, emulsifiable concentrates, orthe like. The formulations may include agents in addition to the one ormore polypeptides embodying the invention. For example, compositions mayfurther comprise spreader-sticker adjuvants, stabilizing agents, otherinsecticidal additives, diluents, agents that optimize the rheologicalproperties or stability of the composition, such as, for example,surfactants, emulsifiers, dispersants, or polymers.

In another embodiment, recombinant hosts that express one or morepolypeptides that are embodiments of the invention are applied on ornear a plant susceptible to attack by an insect pest. The recombinanthosts include, but are not limited to, microbial hosts and insectviruses that have been transformed with and express one or more nucleicacid molecules (and thus polypeptides) of embodiments of the invention.In some embodiments, the recombinant host secretes the polypeptide intoits surrounding environment so as to contact an insect pest. In otherembodiments, the recombinant hosts colonize one or more plant tissuessusceptible to insect infestation.

The nucleotide sequences of the embodiments can also be used to isolatecorresponding sequences from other organisms, particularly otherbacteria, and more particularly other Bacillus strains. In this manner,methods such as PCR, hybridization, and the like can be used to identifysuch sequences based on their sequence homology to the sequences setforth herein. Sequences that are selected based on their sequenceidentity to the entire sequences set forth herein or to fragmentsthereof are encompassed by the embodiments. Such sequences includesequences that are orthologs of the disclosed sequences. The term“orthologs” refers to genes derived from a common ancestral gene andwhich are found in different species as a result of speciation. Genesfound in different species are considered orthologs when theirnucleotide sequences and/or their encoded protein sequences sharesubstantial identity as defined elsewhere herein. Functions of orthologsare often highly conserved among species.

In a PCR approach, oligonucleotide primers can be designed for use inPCR reactions to amplify corresponding DNA sequences from cDNA orgenomic DNA extracted from any organism of interest. Methods fordesigning PCR primers and PCR cloning are generally known in the art andare disclosed in Sambrook et al. (1989) Molecular Cloning: A LaboratoryManual (2d ed., Cold Spring Harbor Laboratory Press, Plainview, N.Y.),hereinafter “Sambrook”. See also Innis et al., eds. (1990) PCRProtocols: A Guide to Methods and Applications (Academic Press, NewYork); Innis and Gelfand, eds. (1995) PCR Strategies (Academic Press,New York); and Innis and Gelfand, eds. (1999) PCR Methods Manual(Academic Press, New York). Known methods of PCR include, but are notlimited to, methods using paired primers, nested primers, singlespecific primers, degenerate primers, gene-specific primers,vector-specific primers, partially-mismatched primers, and the like.

In hybridization techniques, all or part of a known nucleotide sequenceis used as a probe that selectively hybridizes to other correspondingnucleotide sequences present in a population of cloned genomic DNAfragments or cDNA fragments (i.e., genomic or cDNA libraries) from achosen organism. The hybridization probes may be genomic DNA fragments,cDNA fragments, RNA fragments, or other oligonucleotides, and may belabeled with a detectable group such as 32P or any other detectablemarker. Thus, for example, probes for hybridization can be made bylabeling synthetic oligonucleotides based on the sequences of theembodiments. Methods for preparation of probes for hybridization and forconstruction of cDNA and genomic libraries are generally known in theart and are disclosed in Sambrook.

For example, an entire sequence disclosed herein, or one or moreportions thereof, may be used as a probe capable of specificallyhybridizing to corresponding sequences and messenger RNAs. To achievespecific hybridization under a variety of conditions, such probesinclude sequences that are unique to the sequences of the embodimentsand are generally at least about 10 or 20 nucleotides in length. Suchprobes may be used to amplify corresponding Cry sequences from a chosenorganism by PCR. This technique may be used to isolate additional codingsequences from a desired organism or as a diagnostic assay to determinethe presence of coding sequences in an organism. Hybridizationtechniques include hybridization screening of plated DNA libraries(either plaques or colonies; see, for example, Sambrook).

Hybridization of such sequences may be carried out under stringentconditions. The term “stringent conditions” or “stringent hybridizationconditions” as used herein refers to conditions under which a probe willhybridize to its target sequence to a detectably greater degree than toother sequences (e.g., at least 2-fold, 5-fold, or 10-fold overbackground). Stringent conditions are sequence-dependent and will bedifferent in different circumstances. By controlling the stringency ofthe hybridization and/or washing conditions, target sequences that are100% complementary to the probe can be identified (homologous probing).Alternatively, stringency conditions can be adjusted to allow somemismatching in sequences so that lower degrees of similarity aredetected (heterologous probing). Generally, a probe is less than about1000 or 500 nucleotides in length.

Typically, stringent conditions will be those in which the saltconcentration is less than about 1.5 M Na ion, typically about 0.01 to1.0 M Na ion concentration (or other salts) at pH 7.0 to 8.3 and thetemperature is at least about 30° C. for short probes (e.g., 10 to 50nucleotides) and at least about 60° C. for long probes (e.g., greaterthan 50 nucleotides). Stringent conditions may also be achieved with theaddition of destabilizing agents such as formamide. Exemplary lowstringency conditions include hybridization with a buffer solution of 30to 35% formamide, 1 M NaCl, 1% SDS (sodium dodecyl sulfate) at 37° C.,and a wash in 1× to 2×SSC (20×SSC=3.0 M NaCl/0.3 M trisodium citrate) at50 to 55° C. Exemplary moderate stringency conditions includehybridization in 40 to 45% formamide, 1.0 M NaCl, 1% SDS at 37° C., anda wash in 0.5× to 1×SSC at 55 to 60° C. Exemplary high stringencyconditions include hybridization in 50% formamide, 1 M NaCl, 1% SDS at37° C., and a final wash in 0.1×SSC at 60 to 65° C. for at least about20 minutes. Optionally, wash buffers may comprise about 0.1% to about 1%SDS. The duration of hybridization is generally less than about 24hours, usually about 4 to about 12 hours.

Specificity is typically the function of post-hybridization washes, thecritical factors being the ionic strength and temperature of the finalwash solution. For DNA-DNA hybrids, the Tm (thermal melting point) canbe approximated from the equation of Meinkoth and Wahl (1984) Anal.Biochem. 138:267-284: Tm=81.5° C.+16.6 (log M)+0.41 (% GC)−0.61 (%form)−500/L; where M is the molarity of monovalent cations, % GC is thepercentage of guanosine and cytosine nucleotides in the DNA, “% form” isthe percentage of formamide in the hybridization solution, and L is thelength of the hybrid in base pairs. The Tm is the temperature (underdefined ionic strength and pH) at which 50% of a complementary targetsequence hybridizes to a perfectly matched probe. Washes are typicallyperformed at least until equilibrium is reached and a low backgroundlevel of hybridization is achieved, such as for 2 hours, 1 hour, or 30minutes.

Tm is reduced by about 1° C. for each 1% of mismatching; thus, Tm,hybridization, and/or wash conditions can be adjusted to hybridize tosequences of the desired identity. For example, if sequences with >90%identity are sought, the Tm can be decreased 10° C. Generally, stringentconditions are selected to be about 5° C. lower than the Tm for thespecific sequence and its complement at a defined ionic strength and pH.However, severely stringent conditions can utilize a hybridizationand/or wash at 1, 2, 3, or 4° C. lower than the Tm; moderately stringentconditions can utilize a hybridization and/or wash at 6, 7, 8, 9, or 10°C. lower than the Tm; low stringency conditions can utilize ahybridization and/or wash at 11, 12, 13, 14, 15, or 20° C. lower thanthe Tm.

Using the equation, hybridization and wash compositions, and desired Tm,those of ordinary skill will understand that variations in thestringency of hybridization and/or wash solutions are inherentlydescribed. If the desired degree of mismatching results in a Tm of lessthan 45° C. (aqueous solution) or 32° C. (formamide solution), the SSCconcentration can be increased so that a higher temperature can be used.An extensive guide to the hybridization of nucleic acids is found inTijssen (1993) Laboratory Techniques in Biochemistry and MolecularBiology—Hybridization with Nucleic Acid Probes, Part I, Chapter 2(Elsevier, New York); and Ausubel et al., eds. (1995) Current Protocolsin Molecular Biology, Chapter 2 (Greene Publishing andWiley-Interscience, New York). See also Sambrook. Thus, isolatedsequences that encode a Cry protein of the embodiments and hybridizeunder stringent conditions to the Cry sequences disclosed herein, or tofragments thereof, are encompassed by the embodiments.

Preferably, a Cry1 and Cry2 polypeptide are produced by a transgenicplant, thereby making the plant resistant to attack from a target pestand providing synergistic resistance to at least one target pest. Adiscussion of production of such transgenic plants is provided below.

Production of Transgenic Plants

Any method known in the art can be used for transforming a plant orplant cell with a nucleic acid molecule of an embodiment of the presentinvention. Nucleic acid molecules can be incorporated into plant DNA(e.g., genomic DNA or chloroplast DNA) or be maintained withoutinsertion into the plant DNA (e.g., through the use of artificialchromosomes). Suitable methods of introducing nucleic acid moleculesinto plant cells include microinjection (Crossway et al., Biotechniques4:320-334 (1986)); electroporation (Riggs et al., Proc. Natl. Acad.Sci., 83:5602-5606 (1986); D'Halluin et al., Plant Cell, 4:1495-1505(1992)); Agrobacterium-mediated transformation (U.S. Pat. Nos. 5,563,055and 5,981,840; Osjoda et al., Nature Biotechnology, 14:745-750 (1996);Horsch et al., Science, 233:496-498 (1984); Fraley et al., Proc. Natl.Acad. Sci., 80:4803 (1983); Fütterer et al., Gene transfer to plants,213-263 (Potrykus 1995); direct gene transfer (Paszkowski et al., EMBOJ. 3:2717-2722 (1984)); ballistic particle acceleration (U.S. Pat. Nos.4,945,050, 5,879,918, 5,886,244, and 5,932,782; Tomes et al., Direct DNATransfer into Intact Plant Cells via Microprojectile Bombardment, PlantCell, Tissue, and Organ Culture: Fundamental Methods (Gamborg & Phillips1995); and McCabe et al., Biotechnology, 6:923-926 (1988));virus-mediated transformation (U.S. Pat. Nos. 5,889,191, 5,889,190,5,866,785, 5,589,367 and 5,316,931); pollen transformation (De Wet etal., Experimental Manipulation of Ovule Tissues, 197-209 (Chapman et al.1985)); Lec 1 transformation (U.S. patent application Ser. No.09/435,054; International Publication No. WO 00/28058); whisker-mediatedtransformation (Kaeppler et al., Plant Cell Reports, 9:415-418 (1990);Kaeppler et al., Theor. Appl. Genet., 84:560-566 (1992)); andchloroplast transformation technology (Bogorad, Trends in Biotechnology,18:257-263 (2000); Ramesh et al., Methods Mol Biol., 274:301-7 (2004);Hou et al., Transgenic Res., 12:111-4 (2003); Kindle et al., Proc. Natl.Acad. Sci., 88:1721-5 (1991); Bateman & Purton, Mol Gen Genet.,263:404-10 (2000); Sidorov et al., Plant J., 19:209-216 (1999)).

The choice of transformation protocols used for generating transgenicplants and plant cells can vary depending on the type of plant or plantcell, i.e., monocot or dicot, targeted for transformation. Examples oftransformation protocols particularly suited for a particular plant typeinclude those for: potato (Tu et al., Plant Molecular Biology,37:829-838 (1998); Chong et al., Transgenic Research, 9:71-78 (2000));soybean (Christou et al., Plant Physiol., 87:671-674 (1988); McCabe etal., BioTechnology, 6:923-926 (1988); Finer & McMullen, In Vitro CellDev. Biol., 27P:175-182 (1991); Singh et al., Theor. Appl. Genet.,96:319-324 (1998)); maize (Klein et al., Proc. Natl. Acad. Sci.,85:4305-4309 (1988); Klein et al., Biotechnology, 6:559-563 (1988);Klein et al., Plant Physiol., 91:440-444 (1988); Fromm et al.,Biotechnology, 8:833-839 (1990); Tomes et al., Direct DNA Transfer intoIntact Plant Cells via Microprojectile Bombardment, Plant Cell, Tissue,and Organ Culture: Fundamental Methods (Gamborg & Phillips 1995)); andcereals (Hooykaas-Van Slogteren et al., Nature 311:763-764 (1984); U.S.Pat. No. 5,736,369).

In some embodiments, more than one construct is used for transformationin the generation of transgenic plants and plant cells. Multipleconstructs may be included in cis or trans positions. In preferredembodiments, each construct has a promoter and other regulatorysequences. Embodiments of the invention relate to combinations ofdifferent Cry1 and Cry2 proteins resulting in a synergistic effectagainst target pests such as those disclosed herein. By way of example,the Cry1 protein may be the polypeptide disclosed in SEQ ID NO:1 or 4,or a polypeptide that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%,97%, 98%, 99%, 99.5%, or 99.75% identical to the polypeptide of SEQ IDNO:1 or 4. By way of further example, the Cry2 protein may be thepolypeptide disclosed in SEQ ID NO:2, or a polypeptide that is at least90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5%, or 99.75%identical to the polypeptide of SEQ ID NO:2. As a result, a nucleic acidencoding such a Cry1 (such as, for example, the nucleic acid disclosedin SEQ ID NO:3) or Cry2 protein may be used in such a construct.

Transformed plant cells which are derived by any of the abovetransformation techniques can be cultured to regenerate a whole plantwhich possesses the transformed genotype and thus the desired phenotype.Such regeneration techniques rely on manipulation of certainphytohormones in a tissue culture growth medium, typically relying on abiocide and/or herbicide marker that has been introduced together withthe desired nucleotide sequences. Plant regeneration from culturedprotoplasts is described in the art (e.g., Evans et al., ProtoplastsIsolation and Culture, Handbook of Plant Cell Culture, 124-176(MacMillilan Publishing Co. 1983); and Binding, Regeneration of Plants,Plant Protoplasts, 21-73 (CRC Press, 1985). Regeneration can also beobtained from plant callus, explants, organs, or parts thereof. Suchregeneration techniques are also described in the art (e.g., Klee etal., Ann. Rev. of Plant Phys., 38:467-486 (1987)).

The term “plant” includes whole plants, shoot vegetativeorgans/structures (e.g., leaves, stems and tubers), roots, flowers andfloral organs/structures (e.g., bracts, sepals, petals, stamens,carpels, anthers and ovules), seed (including embryo, endosperm, andseed coat) and fruit (the mature ovary), plant tissue (e.g., vasculartissue, ground tissue, and the like) and cells (e.g. guard cells, eggcells, trichomes and the like), and progeny of same. The class of plantsthat can be used in embodiments of the present invention includes theclass of higher and lower plants amenable to transformation techniques,including angiosperms (monocotyledonous and dicotyledonous plants),gymnosperms, ferns, and multicellular algae. Plants of a variety ofploidy levels, including aneuploid, polyploid, diploid, haploid andhemizygous plants are also included.

Embodiments of the invention may use nucleic acid molecules to conferdesired traits on essentially any plant. Thus, embodiments of theinvention have use over a broad range of plants, including species fromthe genera Allium, Ananas, Anacardium, Apium, Arachis, Asparagus,Athamantha, Atropa, Avena, Bambusa, Beta, Brassica, Bromus, Browallia,Camellia, Cannabis, Carica, Ceratonia, Cicer, Chenopodium, Chicorium,Citrus, Citrullus, Capsicum, Carthamus, Cocos, Coffea, Coix, Cucumis,Cucurbita, Cynodon, Dactylis, Datura, Daucus, Dianthus, Digitalis,Dioscorea, Elaeis, Eliusine, Euphorbia, Festuca, Ficus, Fragaria,Geranium, Glycine, Graminae, Gossypium, Helianthus, Heterocallis, Hevea,Hibiscus, Hordeum, Hyoscyamus, Ipomoea, Lactuca, Lathyrus, Lens, Lilium,Linum, Lolium, Lotus, Lupinus, Lycopersicon, Macadamia, Macrophylla,Malus, Mangifera, Manihot, Majorana, Medicago, Musa, Narcissus, Nemesia,Nicotiana, Onobrychis, Olea, Olyreae, Oryza, Panicum, Panieum,Pannisetum, Petunia, Pelargonium, Persea, Pharoideae, Phaseolus, Phleum,Picea, Poa, Pinus, Pistachia, Pisum, Populus, Pseudotsuga, Pyrus,Prunus, Pseutotsuga, Psidium, Quercus, Ranunculus, Raphanus, Ribes,Ricinus, Rhododendron, Rosa, Saccharum, Salpiglossis, Secale, Senecio,Setaria, Sequoia, Sinapis, Solanum, Sorghum, Stenotaphrum, Theobromus,Trigonella, Trifolium, Triticum, Tsuga, Tulipa, Vicia, Vitis, Vigna, andZea.

In specific embodiments, transgenic plants are maize, potato, rice,soybean, alfalfa, sunflower, canola, or cotton plants.

Transgenic plants may be grown and pollinated with either the sametransformed strain or different strains. Two or more generations of theplants may be grown to ensure that expression of the desired nucleicacid molecule, polypeptide and/or phenotypic characteristic is stablymaintained and inherited. One of ordinary skill in the art willrecognize that after the nucleic acid molecule of embodiments of thepresent invention is stably incorporated in transgenic plants andconfirmed to be operable, it can be introduced into other plants bysexual crossing. Any of a number of standard breeding techniques can beused, depending upon the species to be crossed.

In certain embodiments the polynucleotides of the embodiments can bestacked with any combination of polynucleotide sequences of interest inorder to create plants with a desired trait. For example, thepolynucleotides of the embodiments may be stacked with any otherpolynucleotides encoding polypeptides having pesticidal and/orinsecticidal activity, such as other Bt toxic proteins (described in,for example, U.S. Pat. Nos. 5,366,892; 5,747,450; 5,737,514; 5,723,756;5,593,881; and Geiser et al., Gene, 48: 109 (1986)), lectins (Van Dammeet al., Plant Mol. Biol., 24: 825 (1994)), pentin (described in U.S.Pat. No. 5,981,722), and the like. The combinations generated can alsoinclude multiple copies of any one of the polynucleotides of interest.The polynucleotides of the embodiments can also be stacked with anyother gene or combination of genes to produce plants with a variety ofdesired trait combinations including, but not limited to, traitsdesirable for animal feed such as high oil genes (e.g., U.S. Pat. No.6,232,529); balanced amino acids (e.g., hordothionins (U.S. Pat. Nos.5,990,389; 5,885,801; 5,885,802; and 5,703,409); barley high lysine(Williamson et al., Eur. J. Biochem., 165: 99-106 (1987); and WO98/20122) and high methionine proteins (Pedersen et al., J. Biol. Chem.,261: 6279 (1986); Kirihara et al., Gene, 71: 359 (1988); and Musumura etal., Plant Mol. Biol., 12: 123 (1989)); increased digestibility (e.g.,modified storage proteins (U.S. Pat. No. 6,858,778); and thioredoxins(U.S. Pat. No. 7,009,087)); the disclosures of which are hereinincorporated by reference in their entirety.

The polynucleotides of the embodiments can also be stacked with traitsdesirable for disease or herbicide resistance (e.g., fumonisindetoxification genes (U.S. Pat. No. 5,792,931); avirulence and diseaseresistance genes (Jones et al., Science, 266: 789 (1994); Martin et al.,Science, 262: 1432 (1993); Mindrinos et al., Cell, 78:1089 (1994));acetolactate synthase (ALS) mutants that lead to herbicide resistancesuch as the S4 and/or Hra mutations; genes encoding resistance toinhibitors of glutamine synthase such as phosphinothricin or basta(e.g., bar or PAT genes); and glyphosate resistance (EPSPS and GAT(glyphosate acetyl transferase) genes (Castle et al., Science, 304:1151(2004))); and traits desirable for processing or process products suchas high oil (e.g., U.S. Pat. No. 6,232,529); modified oils (e.g., fattyacid desaturase genes (U.S. Pat. No. 5,952,544; WO 94/11516)); modifiedstarches (e.g., ADPG pyrophosphorylases (AGPase), starch synthases (SS),starch branching enzymes (SBE), and starch debranching enzymes (SDBE));and polymers or bioplastics (e.g., U.S. Pat. No. 5,602,321;beta-ketothiolase, polyhydroxybutyrate synthase, and acetoacetyl-CoAreductase (Schubert et al., J. Bacteriol., 170:5837-5847 (1988))facilitate expression of polyhydroxyalkanoates (PHAs)); the disclosuresof which are herein incorporated by reference. One could also combinethe polynucleotides of the embodiments with polynucleotides providingagronomic traits such as male sterility (see, e.g., U.S. Pat. No.5,583,210), stalk strength, flowering time, or transformation technologytraits such as cell cycle regulation or gene targeting (e.g., WO99/61619, WO 00/17364, and WO 99/25821); the disclosures of which areherein incorporated by reference.

These stacked combinations can be created by any method including, butnot limited to, cross-breeding plants by any conventional or TopCrossmethodology, or genetic transformation. If the sequences are stacked bygenetically transforming the plants, the polynucleotide sequences ofinterest can be combined at any time and in any order. For example, atransgenic plant comprising one or more desired traits can be used asthe target to introduce further traits by subsequent transformation. Thetraits can be introduced simultaneously in a co-transformation protocolwith the polynucleotides of interest provided by any combination oftransformation cassettes. For example, if two sequences will beintroduced, the two sequences can be contained in separatetransformation cassettes (trans) or contained on the same transformationcassette (cis). Expression of the sequences can be driven by the samepromoter or by different promoters. In certain cases, it may bedesirable to introduce a transformation cassette that will suppress theexpression of the polynucleotide of interest. This may be combined withany combination of other suppression cassettes or over expressioncassettes to generate the desired combination of traits in the plant. Itis further recognized that polynucleotide sequences can be stacked at adesired genomic location using a site-specific recombination system.See, e.g., WO 99/25821, WO 99/25854, WO 99/25840, WO 99/25855, and WO99/25853, all of which are herein incorporated by reference.

Determination of Expression in Transgenic Plants

Any method known in the art can be used for determining the level ofexpression in a plant of a nucleic acid molecule of embodiments of theinvention or polypeptide encoded therefrom. For example, the expressionlevel in a plant of a polypeptide encoded by a nucleic acid molecule ofembodiments of the invention can be determined by immunoassay,quantitative gel electrophoresis, etc. Expression of nucleic acidmolecules of embodiments of the invention can be measured directly byreverse transcription quantitative PCR (qRT-PCR) of isolated RNA fromthe plant. Additionally, the expression level in a plant of apolypeptide encoded by a nucleic acid molecule of embodiments of theinvention can be determined by the degree to which the plant phenotypeis altered. In one embodiment, enhanced insect resistance is thephenotype to be assayed.

As used herein, “enhanced insect resistance” refers to increasedresistance of a transgenic plant expressing a polypeptide of anembodiment of the invention to consumption and/or infestation by aninsect pest as compared to a plant not expressing a polypeptide of anembodiment of the invention. Enhanced resistance can be measured in anumber of ways. In one embodiment, enhanced resistance is measured bydecreased damage to a plant expressing a polypeptide of an embodiment ofthe invention as compared to a plant not expressing a polypeptide of anembodiment of the invention after the same period of insect incubation.Insect damage can be assessed visually. For example in cotton plants,damage after infestation can be measured by looking directly at cottonplant bolls for signs of consumption by insects. In another embodiment,enhanced resistance is measured by increased crop yield from a plantexpressing a polypeptide of an embodiment of the invention as comparedto a plant not expressing a polypeptide of an embodiment of theinvention after the same period of insect incubation.

Insect pests include insects selected from the orders Coleoptera,Diptera, Hymenoptera, Lepidoptera, Mallophaga, Homoptera, Hemiptera,Orthoptera, Thysanoptera, Dermaptera, Isoptera, Anoplura, Siphonaptera,Trichoptera, etc., particularly Lepidoptera.

Larvae of the order Lepidoptera include, but are not limited to,armyworms, cutworms, loopers, and heliothines in the family NoctuidaeSpodoptera frugiperda JE Smith (fall armyworm); S. exigua Hübner (beetarmyworm); S. litura Fabricius (tobacco cutworm, cluster caterpillar);Mamestra configurata Walker (bertha armyworm); M. brassicae Linnaeus(cabbage moth); Agrotis ipsilon Hufnagel (black cutworm); A. orthogoniaMorrison (western cutworm); A. subterranea Fabricius (granulatecutworm); Alabama argillacea Hübner (cotton leaf worm); Trichoplusia niHübner (cabbage looper); Pseudoplusia includens Walker (soybean looper);Anticarsia gemmatalis Hübner (velvetbean caterpillar); Hypena scabsFabricius (green cloverworm); Heliothis virescens Fabricius (tobaccobudworm); Pseudaletia unipuncta Haworth (armyworm); Athetis mindaraBarnes and Mcdunnough (rough skinned cutworm); Euxoa messoria Harris(darksided cutworm); Earias insulana Boisduval (spiny bollworm); E.vittella Fabricius (spotted bollworm); Helicoverpa armigera Hübner(American bollworm); H. zea Boddie (corn earworm or cotton bollworm);Melanchra picta Harris (zebra caterpillar); Egira (Xylomyges) curialisGrote (citrus cutworm); borers, casebearers, webworms, coneworms, andskeletonizers from the family Pyralidae Ostrinia nubilalis Hübner(European corn borer); Amyelois transitella Walker (naval orangeworm);Anagasta kuehniella Zeller (Mediterranean flour moth); Cadra cautellaWalker (almond moth); Chilo suppressalis Walker (rice stem borer); C.partellus, (sorghum borer); Corcyra cephalonica Stainton (rice moth);Crambus caliginosellus Clemens (corn root webworm); C. teterrellusZincken (bluegrass webworm); Cnaphalocrocis medinalis Guenee (rice leafroller); Desmia funeralis Hübner (grape leaffolder); Diaphania hyalinataLinnaeus (melon worm); D. nitidalis Stoll (pickleworm); Diatraeagrandiosella Dyar (southwestern corn borer), D. saccharalis Fabricius(surgarcane borer); Eoreuma loftini Dyar (Mexican rice borer); Ephestiaelutella Hübner (tobacco (cacao) moth); Galleria mellonella Linnaeus(greater wax moth); Herpetogramma licarsisalis Walker (sod webworm);Homoeosoma electellum Hulst (sunflower moth); Elasmopalpus lignosellusZeller (lesser cornstalk borer); Achroia grisella Fabricius (lesser waxmoth); Loxostege sticticalis Linnaeus (beet webworm); Orthaga thyrisalisWalker (tea tree web moth); Maruca testulalis Geyer (bean pod borer);Plodia interpunctella Hübner (Indian meal moth); Scirpophaga incertulasWalker (yellow stem borer); Udea rubigalis Guenee (celery leaftier); andleafrollers, budworms, seed worms, and fruit worms in the familyTortricidae Acleris gloverana Walsingham (Western blackheaded budworm);A. variana Fernald (Eastern blackheaded budworm); Archips argyrospilaWalker (fruit tree leaf roller); A. rosana Linnaeus (European leafroller); and other Archips species, Adoxophyes orana Fischer vonRösslerstamm (summer fruit tortrix moth); Cochylis hospes Walsingham(banded sunflower moth); Cydia latiferreana Walsingham (filbertworm); C.pomonella Linnaeus (coding moth); Platynota flavedana Clemens(variegated leafroller); P. stultana Walsingham (omnivorous leafroller);Lobesia botrana Denis & Schiffermüller (European grape vine moth);Spilonota ocellana Denis & Schiffermüller (eyespotted bud moth);Endopiza viteana Clemens (grape berry moth); Eupoecilia ambiguellaHübner (vine moth); Bonagota salubricola Meyrick (Brazilian appleleafroller); Grapholita molesta Busck (oriental fruit moth); Suleimahelianthana Riley (sunflower bud moth); Argyrotaenia spp.; Choristoneuraspp.

Selected other agronomic pests in the order Lepidoptera include, but arenot limited to, Alsophila pometaria Harris (fall cankerworm); Anarsialineatella Zeller (peach twig borer); Anisota senatoria J. E. Smith(orange striped oakworm); Antheraea pernyi Guerin-Méneville (Chinese OakSilkmoth); Bombyx mori Linnaeus (Silkworm); Bucculatrix thurberiellaBusck (cotton leaf perforator); Colias eurytheme Boisduval (alfalfacaterpillar); Datana integerrima Grote & Robinson (walnut caterpillar);Dendrolimus sibiricus Tschetwerikov (Siberian silk moth), Ennomossubsignaria Hübner (elm spanworm); Erannis tiliaria Harris (lindenlooper); Euproctis chrysorrhoea Linnaeus (browntail moth); Harrisinaamericana Guérin-Méneville (grapeleaf skeletonizer); Hemileuca oliviaeCockrell (range caterpillar); Hyphantria cunea Drury (fall webworm);Keiferia lycopersicella Walsingham (tomato pinworm); Lambdinafiscellaria fiscellaria Hulst (Eastern hemlock looper); L. fiscellarialugubrosa Hulst (Western hemlock looper); Leucoma salicis Linnaeus(satin moth); Lymantria dispar Linnaeus (gypsy moth); Manducaquinquemaculata Haworth (five spotted hawk moth, tomato hornworm); M.sexta Haworth (tomato hornworm, tobacco hornworm); Operophtera brumataLinnaeus (winter moth); Paleacrita vernata Peck (spring cankerworm);Papilio cresphontes Cramer (giant swallowtail, orange dog); Phryganidiacalifornica Packard (California oakworm); Phyllocnistis citrellaStainton (citrus leafminer); Phyllonorycter blancardella Fabricius(spotted tentiform leafminer); Pieris brassicae Linnaeus (large whitebutterfly); P. rapae Linnaeus (small white butterfly); P. napi Linnaeus(green veined white butterfly); Platyptilia carduidactyla Riley(artichoke plume moth); Plutella xylostella Linnaeus (diamondback moth);Pectinophora gossypiella Saunders (pink bollworm); Pontia protodiceBoisduval & Leconte (Southern cabbageworm); Sabulodes aegrotata Guenée(omnivorous looper); Schizura concinna J. E. Smith (red humpedcaterpillar); Sitotroga cerealella Olivier (Angoumois grain moth);Thaumetopoea pityocampa Schiffermuller (pine processionary caterpillar);Tineola bisselliella Hummel (webbing clothesmoth); Tuta absoluta Meyrick(tomato leafminer); Yponomeuta padella Linnaeus (ermine moth); Heliothissubflexa Guenée; Malacosoma spp. and Orgyia spp.

In particular embodiments, the insect pests are from the order ofLepidopteran insects including European corn borer, e.g., Ostrinianubilalis; corn earworm, e.g., Helicoverpa zea; common stalk borer,e.g., Papiapema nebris; armyworm, e.g., Pseudaletia unipuncta;Southwestern corn borer, e.g., Diatraea grandiosella; black cutworm,e.g., Agrotis ipsilon; fall armyworm, e.g., Spodoptera frugiperda; beetarmyworm, e.g., Spodoptera exigua; and diamond-back moth, e.g., Plutellaxylostella. In specific embodiments, the insect pests are European cornborer, Ostrinia nubilalis, and corn earworm Helicoverpa zea.

Determinations can be made using whole plants, tissues thereof, or plantcell culture.

All publications and patent applications in this specification areindicative of the level of ordinary skill in the art to whichembodiments of this invention pertain. All publications and patentapplications are herein incorporated by reference to the same extent asif each individual publication or patent application was specificallyand individually indicated by reference. The disclosure of eachreference set forth herein is incorporated herein by reference in itsentirety.

EXAMPLES

Embodiments of this invention can be better understood by reference tothe following examples. The foregoing and following description ofembodiments of the present invention and the various embodiments are notintended to limit the claims, but rather are illustrative thereof.Therefore, it will be understood that the claims are not limited to thespecific details of these examples. It will be appreciated by thoseskilled in the art that other embodiments of the invention may bepracticed without departing from the spirit and the scope of thedisclosure, the scope of which is defined by the appended claims.

Example 1

The evaluation of potential synergism between Bt proteins IP1-88 (aCry1) and IP2-127 (a Cry2) using the bioassay method according to Colby,S. R., Calculating synergistic and antagonistic responses of herbicidecombinations, Weeds, 15(1):20-22 (1967). Bt proteins IP1-88 (a Cry1) andIP2-127 (a Cry2) were utilized as test substances to qualitativelyconfirm the presence and resultant effect of the Bt proteins. Evaluationof the interactive effects between the two insecticidal compounds wasrequired to understand the effectiveness of the two toxins stacked intransgenic plants. Resultant synergy was examined using neonate larvaeof European corn borer (ECB), Ostrinia nubilalis.

Standardized Lepidoptera LC50 diet incorporation bioassays were utilizedto evaluate the effects of insecticidal proteins Cry1 and Cry2 onLepidoptera larvae (referring to the immature stage of an insect betweenthe egg and pupal stage of an insect with complete metamorphosis). Allsynergism experiments were conducted in completely randomized designswith 5 replications. Each replicate consisted of eight wells in a96-well bioassay plate. There were two basic doses/treatments for eachprotein based on preliminary data, one close to but <LC50s based onmortality (M) data (as M1×), and the other close to but <IC50s based onresponse (R) data (as R1×, mortality+severe stunted or <0.1 mg/larva).Apart from the basic 1×:1× ratio, higher doses using 2× dose for one ofthe two proteins might be also used (1×:2× or 2×:1×). The insecticidalproteins were combined with a Lepidoptera specific artificial diet tocreate the bioassay diet. Ingredients including boiling water, agar(SeaPlaque), agar (NuSeive), cooling water and Southland Premix wereused for the diet. The diet was dispensed and combined with the proteinsin 96-well plates and one neonate larva was placed in each well.

All plates in bioassays were placed in a growth chamber with a targettemperature of 27±1° C. and relative humidity of >60%. Approximately 4days after initiation of each bioassay, mortality and severe stunted(ss, <0.1 mg/larva) counts were scored. Data analysis was based on thefollowing: X=Observed result from Compound A at dose p; Y=Observedresult from Compound B at dose q; E=Expected result for mixture of A andB at dose (p+q) if there is no synergy or antagonism (assuming responsesrange from 0 to 100), whereby E=X+(100˜X)(Y/100)=X+Y−(X*Y)/100; ifobserved value is greater than expected result (Obs>E): synergism; ifobserved value is similar as expected result (Obs=E): additive; and ifobserved value is less than expected result (Obs<E): antagonism. Resultsprovided in Table 1 below showed synergism on ECB in the mixture ofIP1-88 and IP2-127.

TABLE 1 Mortality of ECB caused by IP1-88 or IP2-127 alone and inmixture (n = 40, 4 d at 27° C.) Protein in Expected single or Observed %mortality, combination Dose % mortality* Colby's equation IP 1-88 M1x32.5 — M2x 23.1 — IP2-127 M1x 7.7 — M2x 20.5 — IP1-88: IP2-127 M1x: 1x63.2 37.7 M1x: 2x 81.6 46.4 M2x: 1x 66.7 29.0 *Corrected data based onAbbott equation with CK mortality < 2.5%.

Example 2

Bt proteins IP1-88 (a Cry1) and IP2-127 (a Cry2), as well as additionalproteins were utilized as test substances to further confirm thepresence and resultant effect of the Bt proteins, according to the samemethods of Example 1. Both European corn borers (ECB) and corn earworms(CEW), Helicoverpa zea, were used in the bioassays. The observedresponse (mortality+ss) of both ECB and CEW in two of three mixturetreatments was evidently higher than expected mortality based on Colby'sequation (results provided in Table 2), also indicative of synergismbetween IP1-88 and IP2-127 for both ECB and CEW.

TABLE 2 Response (mortality + ss) of ECB and CEW caused by IP1-88 orIP2- 127 alone and in mixture (n = 40, 4 d at 27° C.) Protein inObserved/ single or expected combination Dose % response ECB CEW IP 1-88R1x Observed 31.6 19.4 R2x Observed 94.5 27.8 IP2-127 R1x Observed 7.721.5 R2x Observed 20.5 83.8 IP1-88: IP2-127 R1x: 1x Observed 94.7 86.8Expected 36.9 36.7 R1x: 2x Observed 76.9 94.7 Expected 45.6 86.9 R2x: 1xObserved 66.7 68.4 Expected 94.9 36.7

Example 3

Bt proteins Cry1Ah and IP2-127 (a Cry2), as well as additional proteinswere utilized as test substances to further confirm the presence andresultant effect of the Bt proteins, according to the same methods ofExample 1. Both European corn borers (ECB) and corn earworms (CEW),Helicoverpa zea, were used in the bioassays. The observed mortality andresponse (mortality+ss) of both ECB and CEW in the mixture treatmentswas higher than expected based on Colby's equation (results provided inTable 3), also indicative of synergism between Cry1Ah and IP2-127.

TABLE 3 Mortality (mort) and response (resp; mortality + ss) of ECB andCEW caused by Cry1Ah or IP2-127 alone and in mixture. (Trial 1: n = 40,trial 2: n = 32; both 4 d at 27° C.) Protein in single Observed/expectedECB - trial 1 CEW - trial 1 ECB - trial 2 CEW - trial 2 or combinationDose % response % mort % resp % mort % resp % mort % resp % mort % respCry1Ah R1x Observed 59.5 50.6 28.2 23.7 30.2 62.5 45.1 40.9 R2x Observed77.2 92.2 66.7 44.7 30.2 75.0 70.9 70.4 IP2-127 R1x Observed 28.8 6.921.7 7.9 59.4 55.3 11.9 34.9 R2x Observed 72.6 33.3 26.3 34.2 67.7 73.342.4 62.7 Cry1Ah:1P2-127 R1x:1x Observed 74.0 65.4 69.9 69.5 77.0 92.962.8 72.9 Expected 71.2 54.0 43.8 29.7 71.6 83.2 51.6 61.5 R1x:2xObserved 92.2 82.0 74.0 65.8 93.4 100.0 79.7 96.6 Expected 88.9 67.147.1 49.8 77.5 90.0 68.4 78.0 R2x:1x Observed 92.2 75.4 81.4 62.2 54.189.7 86.9 90.2 Expected 83.8 92.7 73.9 49.1 71.6 88.8 74.4 80.8

What is claimed is:
 1. A method of reducing pest damage in a transgenicplant comprising: planting a first transgenic plant seed, wherein thefirst transgenic plant seed comprises a first transgene and a secondtransgene, wherein the first transgene causes expression of a Cry1protein in a plant, wherein the Cry1 protein is selected from the groupconsisting of (a) SEQ ID NO:1, (b) SEQ ID NO:4, and (c) a polypeptidethat is at least 90% identical to the amino acid sequence of SEQ ID NO:1or SEQ ID NO:4; and the second transgene causes expression of a Cry2protein in a plant, wherein the Cry2 protein is selected from the groupconsisting of (a) SEQ ID NO:2 and (b) a polypeptide that is at least 90%identical to the amino acid sequence of SEQ ID NO:2; thereby reducingdamage caused by a first target pest to a plant grown from the firsttransgenic plant seed.
 2. The method of claim 1 wherein the transgenicplant is maize.
 3. The method of claim 1 wherein the first target pestis a member of order Lepidoptera.
 4. The method of claim 3 wherein thefirst target pest is selected from the group consisting of European cornborer and corn earworm.
 5. The method of claim 1 further comprisingtreating the first transgenic plant seed with a pesticidal agent.
 6. Themethod of claim 5 wherein the pesticidal agent is selected from thegroup consisting of: an insecticide, an acaricide, a nematicide, afungicide, a bactericide, a herbicide, or a combination thereof.
 7. Themethod of claim 6 wherein the pesticidal agent is an insecticide.
 8. Themethod of claim 7 wherein the insecticide is selected from the groupconsisting of: a pyrethrin, a synthetic pyrethrin, an oxadizine, achloronicotinyl, a nitroguanidine, a triazole, an organophosphate, apyrrol, a pyrazole, a phenol pyrazole, a diacylhydrazine, abiological/fermentation product, a carbamate, or a combination thereof.9. The method of claim 1 wherein the first transgenic plant seed furthercomprises a herbicide resistance gene.
 10. The method of claim 9 whereinthe herbicide resistance gene is selected from the group consisting of:glyphosate N-acetyltransferase (GAT), 5-enolpyruvylshikimate-3-phosphatesynthase (EPSPS), phosphinothricin N-acetyltransferase (PAT) or acombination thereof.
 11. A method for providing synergistic insecticidalactivity against at least one pest comprising: providing a firsttransgenic plant, wherein the first transgenic plant expresses aCry1-derived insecticidal polypeptide and a Cry2-derived insecticidalpolypeptide, wherein the Cry1-derived insecticidal polypeptide comprisesa polypeptide selected from the group consisting of: (a) SEQ ID NO:1 and(b) SEQ ID NO:4, and (c) a polypeptide that is at least 90% identical tothe amino acid sequence of SEQ ID NO:1 or SEQ ID NO:4; and wherein theCry2-derived insecticidal polypeptide comprises a polypeptide selectedfrom the group consisting of (a) SEQ ID NO:2 and (b) a polypeptide thatis at least 90% identical to the amino acid sequence of SEQ ID NO:2;thereby resulting in synergistic insect resistance against a firsttarget pest.
 12. The method of claim 11 wherein the transgenic plant ismaize.
 13. The method of claim 11 wherein the first target pest is amember of order Lepidoptera.
 14. The method of claim 13 wherein thefirst target pest is selected from the group consisting of European cornborer and corn earworm.
 15. The method of claim 11 further comprisingtreating the first transgenic plant seed with a pesticidal agent. 16.The method of claim 15 wherein the pesticidal agent is selected from thegroup consisting of: an insecticide, an acaricide, a nematicide, afungicide, a bactericide, a herbicide, or a combination thereof.
 17. Themethod of claim 16 wherein the pesticidal agent is an insecticide. 18.The method of claim 17 wherein the insecticide is selected from thegroup consisting of: a pyrethrin, a synthetic pyrethrin, an oxadizine, achloronicotinyl, a nitroguanidine, a triazole, an organophosphate, apyrrol, a pyrazole, a phenol pyrazole, a diacylhydrazine, abiological/fermentation product, a carbamate, or a combination thereof.19. The method of claim 11 wherein the first transgenic plant furthercomprises a herbicide resistance gene.
 20. The method of claim 19wherein the herbicide resistance gene is selected from the groupconsisting of: glyphosate N-acetyltransferase (GAT),5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), phosphinothricinN-acetyltransferase (PAT) or a combination thereof.
 21. A method ofreducing pest damage in a transgenic plant comprising: planting a firsttransgenic plant seed, wherein the first transgenic plant seed comprisesa first transgene and a second transgene, wherein the first transgenecauses expression of a Cry1 protein in a plant and the second transgenecauses expression of a Cry2 protein in a plant, the Cry1 proteinselected from the group consisting of the polypeptide of SEQ ID NO:1 andthe polypeptide of SEQ ID NO:4; and the Cry2 protein comprising thepolypeptide of SEQ ID NO: 2, thereby reducing damage caused by a firsttarget pest to a plant grown from the first transgenic plant seed. 22.The method of claim 21 wherein the transgenic plant is maize.
 23. Themethod of claim 21 wherein the first target pest is a member of orderLepidoptera.
 24. The method of claim 23 wherein the first target pest isselected from the group consisting of European corn borer and cornearworm.
 25. A transgenic plant comprising a first transgene and asecond transgene, wherein the first transgene causes expression of aCry1 protein in a plant and the second transgene causes expression of aCry2 protein in a plant.
 26. The transgenic plant of claim 25, whereinthe Cry1 protein selected from the group consisting of the polypeptideof SEQ ID NO:1 and the polypeptide of SEQ ID NO:4; and wherein the Cry2protein comprises the polypeptide of SEQ ID NO: 2.